| Arid and semi-arid regions Tail lake side retreat and formation of dry lakebed secondarysalt desert landscape, Its material mainly composed of lake facies of loose salt-rich andfine-grained sediments.In the natural soil, soil aggregate structure is less than0.25mm is called soil microaggregates. In this study, the Ebinur Lake dry lakebed in Western Xinjiang Junggar basin asthe study area, through the methods of selecting a typical transect and fieldsampling, analysis Ebinur dry lakebed topsoil micro-aggregate size distribution; research oftopsoil micro-aggregate size distribution characteristics under the different environmentalfactors; to explore the distribution characteristics of the Ebinur Lake dry lakebed surfacesoil micro aggregates the influence of dust emission, and provide scientific basis forthe arid area oasis rump Lake regulation and management and salt dust storm disasterprevention. The main conclusions are as follows:(1) Surface micelles distribution granularity content display:More average content in63-90μm and135-450μm within the scope of the study areamicelle granule size, maximum value of each particle can be seen, the maximum content ofhigh distribution in63-280μm range, size distribution of the minimum value in0-63μm and280-2000μm.6kinds of texture type micro aggregate size is composed of very fine sand and finesand percent content and are respectively54.2%,60.3%,36.1%,66.9%,65.6%,39.2%, medium sand and coarse sand grade percentage and are respectively29.8%,23.4%,40.4%,24.9%,20.3%,40%. Can be seen that the percentage content of sand, loam more, sandy clayloam and clay soil micro aggregates size composed of very fine sand and fine sand, percent content of more clay loam and silty clay micelle size composition in the sand and coarse level. 8vegetation types of micro aggregate size is composed of very fine sand and fine sand percent content and are respectively39.6%,52.5%,59.3%,64%,62.6%,35.7%,45.2%,52.4%, medium sand and coarse sand grade percentage and are respectively37.9%,25.6%,26.5%,21.4%,12.5%,40.1%,33.9%,36.2%. It can be seen that the4kinds of desertplants and reed meadow micelle percent more very fine sand and fine sand grain size composition, the other3meadow vegetation and reed micelle percent more sand and coarse level of granularity composition.12types of soil micro aggregates size composition content of very fine sand and fine sand level and are respectively44.9%,37%,48.9%,56.8%,50.1%,74.7%,65.6%,69.3%,61.9%,36.1%,25.8%and45.1%, medium sand and coarse sandgrade percentage and respectively.43.9%,35.3%,26.8%,28.4%,34.9%,18.1%,20.3%,17.8%,24.3%,40.4%,44.5%and33.7%. Can be seen that the sulfursalinized shrub meadow soil, sulphate meadow saline soil, salinized shrub meadow soil, semi fixed sandy soil sulphur salt swamp soil, salinesoil and marsh solonchakchloride typical micro mass percent content of more fine sand and fine sand grain size composition, at the same time, gray brown desert soil, irrigation and cultivation soil, salinized shrub meadow soil, sulphur saline meadow soil, irrigation and cultivation of sulfur saline meadow soil and gray irrigation and cultivation soil micro aggregates size composition in the sand and coarse level percent more. In addition, sulfur saline meadow soil and irrigated sulfur saline meadow soil micro aggregates of very coarsesand grade percentage were17.8%and23.8%, than the same type of very fine sand and sand percent content.(2) The lognormal distribution model fitting showed:Sand, loam, sandy clay loam and clay soil micro aggregates size by very fine sand and medium sand group, silty clay and clay loam soil micro aggregates size by very fine sand, sand and coarse sand in group composition, their corresponding mass median diameterwas84μ m,188μ m and994μ m; standard deviation values were1.47,1.38and1.40;the percentage were40%,48%and12%. Haloxylon desert and4kinds of desert plants in micro aggregate size are composedof very fine sand and medium sand group, winter and spring wheat, vegetation, including Populous reed meadow vegetation types and micro aggregate size are composed of veryfine sand, medium sand group group and coarse level groups, corresponding to it the mass media diameter were84μm,188μm and960μm; standard deviation values were1.3,1.28and1.29; the percentage were39%,49%and12%.Grey brown desert soil, sculpture salt shrubby meadow soil, sulphate meadow salinesoil, salinized shrub meadow soil, semi fixed sandy soil, saline marsh, sulfur chloride saline soil and bog soils typical micro aggregate size are composed of very fine sand and medium sand group, irrigation and cultivation soil, sculpture saline meadow soil irrigated saline meadow soil, sulfur and ash irrigation and cultivation soil micro aggregates size respectively by very fine sand, sand and coarse sand in group composition, their corresponding mass median diameter were83μ m,190μ m and1000μ m; standard deviation values were1.32,1.42and1.37; the percentage were38%,48%and14%.(3) By DPM model shows, in many different texture, very fine sand content of sand, loam and clay, are more prone to dust emission than other texture; in the different vegetation types, morefine sand content of Haloxylon desert and other four kinds of desert vegetation,more prone to dust release than other vegetation types; different soil types, morefine sand forest shrub meadow soil salt content of sulfur, sulfur saline marsh and chloride typical soils, more easily than other vegetation types occurring dust release. |
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